# "Can not update MCU 'canbridge' config as it is shutdown" on RP2040 can bus bridge

**URL:** <https://klipper.discourse.group/t/can-not-update-mcu-canbridge-config-as-it-is-shutdown-on-rp2040-can-bus-bridge/13237>\
**Category:** General Discussion\
**Created:** [January 16, 2024, 10:37pm UTC](https://klipper.discourse.group/t/can-not-update-mcu-canbridge-config-as-it-is-shutdown-on-rp2040-can-bus-bridge/13237 "2024-01-16T22:37:32Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Arakon](https://avatars.discourse-cdn.com/v4/letter/a/f1d935/32.png) [@Arakon](https://klipper.discourse.group/u/Arakon)\
**Post date:** [January 16, 2024, 10:37pm UTC](https://klipper.discourse.group/t/can-not-update-mcu-canbridge-config-as-it-is-shutdown-on-rp2040-can-bus-bridge/13237/1 "2024-01-16T22:37:33Z")

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### Basic Information:

Printer Model: Vz235  
 MCU / Printerboard: SKR3, EBB36, RP2040 Pico with TJA1051 transceiver  
 `klippy.log`  
[klippy-shutdown.zip](https://klipper.discourse.group/uploads/short-url/6nIMIRCSOeWXJuEz3ZuS1gpZ094.zip) (51.7 KB)

### Describe your issue:

The printer is running on a seperate PSU that keeps the Pi and RP2040 running when the printer itself is powered down (24V/220V shut off). Once the power is turned off for a couple of minutes, on restart, I get the above error message.  
I tried adding a different restart method, but they seem to be invalid for USB canbus bridge devices.

Any idea how to enforce a firmware restart on that MCU on power-up?

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**Author:** ![LifeOfBrian](https://yyz2.discourse-cdn.com/free1/user_avatar/klipper.discourse.group/lifeofbrian/32/2380_2.png) [@LifeOfBrian](https://klipper.discourse.group/u/LifeOfBrian)\
**Post date:** [January 17, 2024, 7:47am UTC](https://klipper.discourse.group/t/can-not-update-mcu-canbridge-config-as-it-is-shutdown-on-rp2040-can-bus-bridge/13237/2 "2024-01-17T07:47:36Z")

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What are the settings in the interfaces for the respective can devices ( `/etc/network/interfaces.d/can0`)?

Does it look like this:

```auto
allow-hotplug can0
iface can0 can static
    bitrate 1000000
    up ifconfig $IFACE txqueuelen 128

```

?

Maybe you should try `auto can0` in the first line.

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**Author:** ![Arakon](https://avatars.discourse-cdn.com/v4/letter/a/f1d935/32.png) [@Arakon](https://klipper.discourse.group/u/Arakon)\
**Post date:** [January 17, 2024, 10:42am UTC](https://klipper.discourse.group/t/can-not-update-mcu-canbridge-config-as-it-is-shutdown-on-rp2040-can-bus-bridge/13237/3 "2024-01-17T10:42:58Z")

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I use a larger txqueuelen, but yeah, otherwise like that. I also tried auto just now (and bringing the can0 network down and back up), with the same error.  
Also, since the interface is constantly powered, it shouldn’t go down at all… it seems almost like Klipper is shutting it down when the printer is powered off (maybe due to connection error? since the EBB36 drops off the network), and then won’t bring it back up when powered again.

Edit: To add - Moonraker is already configured to ` restart_klipper_when_powered: true`

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**Author:** ![system](https://global.discourse-cdn.com/free1/uploads/klipper/original/1X/64419bf2aac6639e6ef5cef200dcd456b0a01ac3.png) [@system](https://klipper.discourse.group/u/system)\
**Post date:** [March 17, 2024, 10:43am UTC](https://klipper.discourse.group/t/can-not-update-mcu-canbridge-config-as-it-is-shutdown-on-rp2040-can-bus-bridge/13237/4 "2024-03-17T10:43:35Z")

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